Molecular and functional characteristics of purified gum from Australian chia seeds

•The extraction and purification protocols for chia seed gum (CSG) are described.•13C NMR and HPLC analysis confirmed the xylose-to-glucose ratio of CSG to be 2:1.•CSG was found to be resistant to pyrolytic degradation up to 244°C.•CSG was found to be more effective stabilizer than guar and locust bean gum.•CSG showed strong anionic characteristics within the pH range of 2.0–12.0. Chia seed gum (CSG) was extracted from the seed coat of Salvia hispanica, purified in the laboratory and its chemical composition and functional properties were investigated. CSG was found to comprise 93.8% carbohydrate consisting of xylose, glucose, arabinose, galactose, glucuronic acid and galacturonic acid as monosaccharide units. The presence of uronic acids was reflected in the anionic behavior of the CSG solution over a wide range of pH (≥1.8). The solubility of CSG increased slightly with temperature and pH of the aqueous medium. CSG was able to resist pyrolytic decomposition at temperatures well in excess of 250°C, and exhibited a high water holding capacity (23 times of its own weight). The surface activity and emulsifying properties of CSG were found to be either superior or comparable to other common gums and industrial polysaccharides indicating the potential of CSG as an effective thickener and stabilizer of processed foods.